There is an image forming apparatus that turns off, in association with operation for opening an armor cover, an interlock switch that locks driving of the image forming apparatus. In the image forming apparatus that switches the interlock switch with the armor cover, when it is attempted to replace a toner cartridge during image forming operation, the interlock switch is turned off at a point when the armor cover is opened. As a result, the image forming operation of the image forming apparatus is stopped and productivity falls.
On the other hand, there is an image forming apparatus that switches an interlock switch using a sheet conveying unit rather than an armor cover and prevents fall in productivity of the image forming apparatus. There is a sheet conveying unit in which a sheet conveying unit motor is connected to a driver in a plug-in system to realize a reduction in size and cost. In the sheet conveying unit of the plug-in system, when a plug suddenly slips off during driving of the motor, plug slip-off detection of the driver is locked to cause breakage of a driver substrate.
Therefore, when the interlock switch is switched by using the sheet conveying unit of the plug-in system, when the interlock switch is suddenly turned off while the motor is driving, it is likely that the driver determines that the plug of the sheet conveying unit slips off, locks the plug slip-off detection, and damages the driver substrate.
There is a demand for development of a sheet conveying unit for an image forming apparatus that can realize improvement of productivity of the image forming apparatus and a reduction in size and cost of the sheet conveying unit and obtain safety during maintenance while preventing breakage of a driver substrate of the sheet conveying unit.